ES3019407T3 - Left atrial appendage occluder - Google Patents

Abstract

The present invention relates to a left atrial appendage occluder (10), comprising a sealing disc (100) and a fixation support (200) connected to the sealing disc (100) and located at one side thereof. The fixation support (200) comprises a connection section (210) connected to the sealing disc (100) and plural supports (220). After radiating distally from the connection section (210) and coordinating to form a recessed area (221), the plural supports (220) bend to extend proximally and form plural spaced suspended support segments (222). The support segment (222) has at least one anchoring prong (223) facing the sealing disc (100). The left atrial appendage occluder (10) further comprises a thin film (300), which supports (220) are connected in series through the thin film (300). The present invention effectively restricts the relative position and relative movement between the support segments (222) through the thin film (300), thereby preventing twisting of the support segments (222) when the fixing support (200) is pushed out and released from a delivery sleeve. (Automatic translation with Google Translate, no legal value)

Description

DESCRIPTION

Left atrial appendage occluder

The present invention relates to medical devices, in particular to an occluder for preventing stroke caused by thrombosis in the left atrial appendage due to atrial fibrillation.

Currently, interventional catheterization therapy is widely used to treat diseases, and a variety of materials, devices, and drugs are delivered to the heart, arteries, and veins of the human body. When an occluder is delivered to the heart, arteries, veins, and left atrial appendage using a catheter-based intervention, the complex anatomical structures of the heart and arterial and venous blood vessels, especially the left atrial appendage, require the device to be precisely positioned and to adapt well to the anatomical structure, mechanical requirements, and hemodynamic requirements of the predetermined position. Under the premise of generating only microtrauma to the human body, first, the skin near the blood vessel is punctured, a guide wire is introduced into the blood vessel from the puncture site, one end of a catheter is brought to the predetermined position under the guidance of the guide wire, and the other end of the guide wire is reserved in vitro, and then the apparatus is transferred to the predetermined position by using the catheter and a pusher. During such a procedure, a thin and flexible catheter is required, while the catheter and the guide wire are designed to be visualized under X-rays. After the catheter reaches the predetermined position, the guide wire is withdrawn, and the apparatus is guided to the tail end of the catheter by using an access established by the catheter through the pusher; when it is completely exposed from the tail end of the catheter, the apparatus is released from the pusher. For example, an occluder is placed in the left atrial appendage via catheter-based intervention to prevent left atrial appendage thrombosis that causes atrial fibrillation and embolism caused by the thrombus ascending to the brain; and to prevent systemic embolism caused by the thrombus reaching other parts of the body through the body's blood circulation. Placing an occluder in the left atrial appendage to occlude the left atrial appendage and block blood flow into the left atrial appendage can eliminate the risk of thrombosis forming in the left atrial appendage, thereby preventing narrowing. Currently, the devices are usually connected to a delivery sheath via a thread.

Document CN 102805654 A discloses a left atrial appendage occluder comprising a sealing disc connected to a fixation support, wherein the fixation support comprises a connecting portion and a plurality of supports. The supports form support segments and each segment is provided with at least one anchoring prong.

Document US 2011/0054515 relates to an implantable medical device for insertion into the left atrial appendage that includes a cap attached to a frame. The cap limits the movement of the frame legs during device collapse or expansion, allowing the device to be deployed, retracted, and redeployed without damaging the device or entangling the frame legs.

WO 01/30266 relates to an apparatus for permanent placement across an ostium of a left atrial appendage in a patient, which includes a filter membrane configured to extend across the ostium of the left atrial appendage. The filter membrane has a permeable structure that permits the passage of blood but substantially inhibits the passage of blood clots.

US 2013/0178889 relates to devices, methods, and systems for occluding an opening within body tissue, such as a left atrial appendage. In one example, a medical device includes an occluding portion and an anchoring portion, the anchoring portion being hingedly connected to the occluding portion. With this arrangement, the anchoring portion actuates and pivots relative to the occluding portion between a deployed anchoring position and an undeployed anchoring position.

Document US 2012/0283585 relates to atrial appendage occlusion devices and arrhythmia treatment.

Document WO 2013/060855 relates to a method for manufacturing a medical implant or structures for a medical implant. An improved occluder is presented that does not damage surrounding body tissue. In one example, a method is provided for manufacturing a 3D woven fabric of filaments to form an occluder.

Document US 2003/0181942 relates to an instrument for the percutaneous delivery of blood filtration devices to atrial appendages, which includes a curved access sheath and an administration tube. A compressed filter device attached to a tether is loaded into the delivery tube. The loaded implantation tube is advanced through the prepositioned access sheath to place the device in the deployed position.

Referring to Fig. 1 and Fig. 2, Fig. 1 shows another known left atrial appendage occluder located in an anatomical structure of the heart and the left atrial appendage, and Fig. 2 is a structure diagram of the existing left atrial appendage occluder, wherein 01 means left atrium, 02 means left atrial appendage, and 03 means a cavity wall of the left atrial appendage. The occluder includes a sealing disk 11 and a fixing bracket 12 consisting of a plurality of brackets 13; a fixing anchor (or so-called anchor spike) 15 is provided on each of the brackets 13, and the brackets 13 extend to the spherical ends of the bracket ends 14 from a position where the fixing anchor 15 is located, and are spaced apart from each other; A connecting nut 16 is arranged on the sealing disc 11 of the left atrial appendage occluder.

The occluder has good elasticity, can be contained in a sheath with a width of 2 to 4 mm, transferred to the left atrial appendage 02 through the vascular access, and slowly withdrawn from the sheath tube; the fixing bracket 12 of the occluder will be deployed in the cavity of the left atrial appendage, and the brackets 13 of the fixing bracket 12 will be pressed onto the wall of the left atrial appendage to fit the shape of the left atrial appendage 02, while the fixing anchor 15 of the brackets 13 will penetrate the inner wall 03 of the left atrial appendage, so as to thereby ensure reliable fixation, and, the sealing disc 11 is covered on the ostium of the left atrial appendage 02, as shown in Fig. 1.

Finally, a steel wire connected to the left atrial appendage occluder is released, thereby occluding the left atrial appendage and blocking blood flow into the left atrial appendage.

Known left atrial appendage occluders have the following limitations: the supporting ends of the fixation scaffold are spaced and suspended. When the fixation scaffold is pushed out after being placed in the sheath tube, there is a risk of twisting between the ends of the scaffold, which may result in the scaffold not deploying properly and, therefore, the procedure failing.

Summary of the invention

An object of the present invention is to provide a left atrial appendage occluder, which prevents torsion between the supports.

In accordance with the present invention, there is provided a left atrial appendage occluder as defined in claim 1. The occluder includes a sealing disc and a fixation support that is connected to the sealing disc and located on one side of the sealing disc; the fixation support including a connection portion connected to the sealing disc and a plurality of supports; extending distally from the connection portion and defining a recessed area, the plurality of supports are bent to extend proximally to form a plurality of spaced suspended support segments, the support segment being provided with at least one anchoring prong facing the sealing disc. The left atrial appendage occluder further includes a thin film, all of the supports being connected one after the other through the thin film. At least one anchoring prong penetrates through the thin film. The supports are further provided with a plurality of fixation holes, through which the thin sheet is fixed to the supports by means of suture.

In one embodiment of the present invention, the thin sheet includes at least one annular thin sheet that is fixed over all supports and surrounds the recessed area to expose all or part of the recessed area.

In another embodiment of the present invention, the thin film includes a spherical thin film that further covers the recessed area.

In another embodiment of the present invention, the thickness of a portion of the thin film located in an area surrounding the anchoring spike is greater than or equal to that of the remaining portion of the thin film.

In another embodiment of the present invention, a proximal edge of the thin film is 1 to 5 mm away from a root of the anchoring prong.

In another embodiment of the present invention, after penetrating the thin film, the outwardly extending length of the anchoring spike is between 1 mm and 3 mm. In another embodiment of the present invention, the thin film is made of PET or PTFE or silica gel.

In one embodiment of the present invention, the thin film includes a plurality of superimposed thin film layers.

In one embodiment of the present invention, the thin film includes multiple thin film sheets distributed at intervals on the fixing support along the direction from the distal end to the proximal end.

In the left atrial appendage occluder according to one embodiment of the present invention, the supports include a plurality of guide segments, a plurality of branch segments, and a plurality of suspended support segments successively radiating outwardly distally from the connection portion. In another embodiment of the present invention, the plurality of guide segments are coordinated with each other to define a recessed area with the connection portion as a center; an end of each guide segment remote from the connection portion is respectively connected to two branch segments; the two branch segments form an included angle; each branch segment intersects one of the two branch segments corresponding to the adjacent guide segment that is adjacent thereto, and is bent to extend proximally to form the suspended support segments.

Compared with the prior art, the technical solution employed by the present invention has at least the following advantages: the left atrial appendage occluder further includes the thin film through which all supports are connected one after another, the present invention effectively restricts the relative position and relative movement between the support segments through the thin film, to thereby prevent twisting of the support segments when the fixation support is pushed out and released from a delivery sheath.

Brief description of the drawings

The present invention will be further illustrated with reference to the accompanying drawings showing embodiments, in the drawings:

Fig. 1 is a diagram showing a known occluder of the left atrial appendage in an anatomical structure of the heart and the left atrial appendage;

Fig. 2 is a diagram of the structure of the known left atrial appendage occluder;

Figure 3 is a schematic diagram of a left atrial appendage occluder provided by an embodiment of the present invention;

Fig. 4 is a schematic diagram of the left atrial appendage occluder shown in Fig. 3 from another view;

Figures 5 and 6 show a schematic diagram of a fixing bracket of Figure 3;

Fig. 7 shows a local diagram of a support and a thin film of Fig. 3;

Fig. 8 shows a schematic diagram of the left atrial appendage occluder shown in Fig. 3 after being released into the left atrial appendage;

Figure 9 is a schematic diagram of a left atrial appendage occluder provided by another embodiment of the present invention;

Fig. 10 is a schematic diagram of the left atrial appendage occluder shown in Fig. 9 from another view;

Fig. 11 is a schematic diagram of the left atrial appendage occluder as shown in Fig. 9 after being released into the left atrial appendage; and

Fig. 12 is a schematic diagram of the left atrial appendage occluder as shown in Fig. 9 which does not completely occlude an inlet of the left atrial appendage in the process of releasing into the left atrial appendage.

Detailed description of the achievements

In order to understand the object, the technical solution and the advantages of the present invention more clearly, the present invention will be described in more detail with reference to the accompanying drawings and embodiments.

Referring to Fig. 3 to Fig. 8, an embodiment of the present invention provides a left atrial appendage occluder 10 including a sealing disc 100, a fixing bracket 200 connected to the sealing disc 100 and located on one side of the sealing disc 100, and a thin sheet 300 fixed on the fixing bracket 200.

The sealing disc 100 is formed by braiding a nickel titanium wire or a biocompatible polymer wire, and located at the proximal end in relation to the fixation support 200.

The fixing bracket 200 includes a connection portion 210 connected to the sealing disc 100, and a plurality of brackets 220. After radiating distally from the connection portion 210 and coordinating to form a recessed area 221, the plurality of brackets 220 are bent to extend proximally to form a plurality of spaced suspended bracket segments 222, the bracket segments 222 being provided with at least one anchoring prong 223 facing the sealing disc 100. In actual manufacturing, the plurality of brackets 220 may be formed by cutting a nickel-titanium tube from one end thereof along the direction toward the other end, expanded by using a mold, and shaped by heat treatment; The portion of the nickel-titanium tube that is not cut forms the connection portion 210. The number of supports 220 may be determined according to the requirements of the mechanical properties and size specifications, such as six, eight, nine, twelve, and sixteen, etc. During cutting, the anchor spike 223 disposed on the supports 220 is cut at the same time.

Referring to Fig. 5 to Fig. 6, the supports 220 include a plurality of guide segments 224, a plurality of branch segments 225, and a plurality of suspended support segments 222 successively radiating outwardly distally from the connection portion 210. The plurality of guide segments 224 are coordinated with each other to form the recessed area 221 with the connection portion 210 as a center. An end of each guide segment 224 remote from the connection portion 210 is respectively connected to two branch segments 225. The two branch segments 225 form an included angle, preferably an acute angle. Each branch segment 225 intersects one of the two branch segments corresponding to the guide segment 224 adjacent thereto, and bends to extend proximally to form the suspended support segments 222. The support segments 222 are spaced apart from one another. In other words, each guide segment 224, surrounding the connection portion 210, terminates at the two branch segments 225 connected thereto, to form a similar V- or herringbone-like shape; and two adjacent V-shaped or herringbone-shaped structures, after being connected at an end remote from the connection portion 210, extend to form the support segment 222. The support segment 222 is approximately U-shaped, one end thereof connected to the branch segments 225 is provided with an anchor spike 223, and the suspended end thereof is processed to form the ball 226. Referring to Fig. 6, the ends of the guide segments 224 and the branch segments 225 proximate the support segment 222 are all provided with a plurality of fixing holes 227.

However, as shown in FIG. 3 and FIG. 4, the thin film 300 is usually made of PET or PTFE or silica gel material, and may also be made of other thin film having biocompatibility and physical performance that meets the requirements. The thin sheet 300 includes an annular thin sheet fixed on all of the branch segments 225 of the fixing support 200 in a coordinated manner of the anchoring tab 223 and suture, thereby being connected in series to all of the supports 220 to expose all or part of the recessed area 221. After the occluder 10 is released in the left atrial appendage, the thin film 300 constitutes the external surfaces of the supports 220 in contact with the inner wall of the left atrial appendage. Suturing means that the suture passes through the fixing holes 227 and then passes through the annular thin film 300, and then is knotted to fix the thin film 300. As shown in Fig. 7, the width of the thin film 300 may be determined by a position from the anchor spike 223 to the fixing holes 227 of the brackets 220 of the fixing bracket 200 and the annular thin film 300. In the present embodiment, the thin film 300 may extend proximally 1 to 5 mm from the root of the anchor spike 223, and the thin film 300 may extend distally 2 to 10 mm from the fixing holes 227 of the brackets 220 and the annular thin film 300. The thickness of the thin film 300 should meet the following conditions: after penetrating through the thin film 300, The length of the anchoring prong 223 extending outside the thin sheet 300 is equal to or greater than 1 mm and less than or equal to 3 mm, so as to ensure that the anchoring prong 223 does not fall off after being inserted into the left atrial appendage.

Fig. 8 shows a schematic diagram of the left atrial appendage occluder released in the left atrial appendage, as shown in Fig. 8, when the fixing bracket 200 is placed on the left atrial appendage, the fixing bracket 200 and the annular thin film 300 are deployed in the state shown in Fig. 8, the brackets 220 of the fixing bracket 200 and the annular thin film 300 are laminated together on the inner wall 03 of the left atrial appendage, the contact surface between the fixing bracket 200 and the inner wall 03 is a cylindrical surface. This is compared with the known left atrial appendage occluder, as shown in Fig. 1, in which only each bracket 220 and the inner wall 03 are in contact, the contact area being tens of times larger. In this way, the stress is distributed more evenly along the inner wall 03, so that the penetration length of the anchor spikes 223 of the brackets 220 is approximately the same in the inner wall 03. At the same time, the stress per unit area is lower, thus avoiding damage to the inner wall 03 caused by excessive stress at a certain location.

Furthermore, the thin film 300 plays a role of effectively restraining the relative position and relative movement between the supports 220. The thin film 300 has soft, thin, compressible and elastic characteristics, so that the thin film 300 can always be retained on the supports 220 and folded and unfolded together with the supports 220 in the process of placing the fixing support 200 in a delivery sheath and then pushing it out from the delivery sheath, thereby reducing or even avoiding the risk of twisting the supports 220, and ensuring the smooth operation of the method. Furthermore, due to the structural and size characteristics of the annular thin sheet 300, the edge thereof being at a certain distance from the root of the anchoring prong 223, when the anchoring prong 223 penetrates the inner wall 03 of the left atrial appendage to a certain depth, the annular thin sheet 300 will prevent the anchoring prong 23 from moving deep into the wall 03, so that the depth of the anchoring prong 223 penetrating the wall 03 is controllable and the extensive damage to the wall 03 caused by uneven stress is decreased. Furthermore, in an extreme case, such as when the wall 03 is pierced by an anchoring spike 223, in accordance with the existing left atrial appendage occluder, blood will flow out of the wall 03 and flow into the inside of the left atrial appendage and then leak into the pericardial cavity from the punctured position, resulting in pericardial effusion, seriously causing cardiac arrest and threatening life. However, in the present embodiment, once the wall 03 is pierced by the anchoring spike 223, the thin film 300 will immediately cover the punctured position and facilitate the formation of microthrombi in the vicinity, the thrombus will block the hole resulting from the perforation, thereby preventing blood from leaking into the pericardial cavity and reducing the risk of pericardial effusion and even cardiac arrest. At the same time, the thin film can accelerate the thrombosis of blood in the left atrial appendage and then muscle, and accelerate the muscularization process of the left atrial appendage.

9 to 12 , a left atrial appendage occluder 20 provided by another embodiment of the present invention has a structure similar to that of the left atrial appendage occluder 10, including a sealing disc 400, a fixing bracket 500 connected to the sealing disc 400 and positioned on one side of the sealing disc 400, and a thin film 600 fixed on the fixing bracket 500. The difference between the occluder 20 and the left atrial appendage occluder 10 is that the thin film 600 is spherical, a proximal edge thereof is located at a distance of 1 to 5 mm from the root of an anchoring tab 523, and a distal portion of the thin film 600 covers the entire recessed area (covered, not shown).

The thin film 600 and the supports 520 are sutured together through the fixing holes 527, 528. Each group of fixing holes 527 and 528 is arranged at the same positions on each support 520. The fixing manner is the same as in the first embodiment.

In addition to the same mechanism of action and advantages as the first embodiment, the thin film 600 further has the following characteristics as follows: in some extreme cases, as shown in Fig. 12, the entrance of the left atrial appendage is not completely sealed by the sealing disc 11 of the left atrial appendage occluder, blood may enter the left atrial appendage along the direction represented by an arrow 05, at this time, the thin film 600 of the second embodiment will act as a second barrier near the entrance into the left atrial appendage, to thereby prevent blood from entering a deeper portion of the left atrial appendage and reduce a risk of thrombosis.

Compared with the previous embodiments, the left atrial appendage occluder of the present embodiment is capable of blocking blood flow entering at a deeper position in the left atrial appendage chamber because the inlet of the left atrial appendage is not completely sealed by the sealing disc 11 of the left atrial appendage occluder, to thereby reduce the risk of thrombosis.

The thin film may have different thicknesses according to different areas. For example, the thickness of a portion of the thin film located around the anchoring prong is greater than or equal to that of the other portions of the thin film. Thus, once the wall of the left atrial appendage is pierced by the anchoring prong, the thickened thin film located around the anchoring prong will more effectively prevent bleeding after the anchoring prong penetrates the left atrial appendage, and accelerate thrombosis. In other embodiments, the thin film comprises laminated films, and more layers of thin film are located around the anchoring prong. For example, the thin film may include a first thin film layer that is a hemispherical thin film and a second thin film layer that is an annular thin film, the first thin film layer and the second thin film layer being laminated in the area surrounding the anchoring prong, to increase the thickness of the thin film in the area surrounding the anchoring prong. In other embodiments, the thin film includes multiple thin film sheets distributed at intervals on the fixing support along the direction from the distal end to the proximal end.

The thin film may be fixed at any suitable position of the supports, such as being fixed at least one of the recessed area, the guide segments, the branch segments and the support segments, provided that the supports in the natural state are connected in series and fixed to the thin film.

Claims (11)

1. A left atrial appendage occluder, comprising a sealing disc (100) and a fixing support (200) connected to the sealing disc (100) and located at one side of the sealing disc (100); the fixing support (200) comprises a connection portion (210) connected to the sealing disc (100) and a plurality of supports (220) extending from the connection portion (210) in a distal direction and bending in a proximal direction, to define a recessed area (221) and form a plurality of spaced suspended support segments (222), each of the support segments being provided with at least one anchoring prong (223) facing the sealing disc (100), characterized in that the left atrial appendage occluder further comprises a thin film (300), at least one anchoring prong (223) penetrating through the thin film (300) and all supports (220) connecting one after the other through the thin film (300), and wherein the supports (220) are further provided with a plurality of fixing holes (227), through which the thin film (300) is fixed to the supports (220) by suturing. 2. The left atrial appendage occluder according to claim 1, wherein the thin sheet (300) comprises at least one annular thin sheet (300) surrounding the recessed area (221) and is connected in series to all of the supports (220) to expose all or a portion of the recessed area (221). 3. The left atrial appendage occluder according to claim 1, wherein the thin film (300) comprises a spherical thin film (300) further covering the recessed area (221). 4. The left atrial appendage occluder according to claim 1, wherein the thickness of a portion of the thin film (300) located in the area surrounding the anchoring prong (223) is greater than or equal to that of the remaining portion of the thin film (300). 5. The left atrial appendage occluder according to claim 1, wherein a proximal edge of the thin plate (300) is located at a distance of 1 to 5 mm from a root of the anchoring prong (223). 6. The left atrial appendage occluder according to claim 1, wherein after penetrating through the thin sheet (300), the length of the anchoring prong (223) extending outward is between 1 mm and 3 mm. 7. The left atrial appendage occluder according to claim 1, wherein the thin film (300) is made of PET or PTFE or silica gel. 8. The left atrial appendage occluder according to claim 1, wherein the thin film (300) comprises a plurality of laminated layers of thin film. 9. The left atrial appendage occluder according to claim 1, wherein the thin sheet (300) comprises multiple sheets of thin sheet (300) distributed at intervals on the fixing support (200) along the direction from the distal end to the proximal end. 10. The left atrial appendage occluder according to claim 1, wherein the supports (220) comprise a plurality of guide segments (224), a plurality of branch segments (225) and a plurality of suspended support segments (222) radiating distally from the connection portion (210). 11. The left atrial appendage occluder according to claim 1, wherein the plurality of guide segments (224) are coordinated with each other to form said recessed area (221) by considering the connection portion (210) as a center; an end of each guide segment (224) remote from the connection portion (210) is respectively connected to two branch segments (225); the two branch segments (225) form an included angle; each branch segment (225) intersects with one of the two branch segments (225) corresponding to the adjacent guide segment (224) that is near it, and is bent to extend proximally to form the suspended support segments (222).